A defining thread of modern scientific thought is skepticism, the tendency to question accepted ideas until evidence is found to confirm or reject them. But what do skeptics do in worlds of magic, aliens, and other matters fantastic?

Science fiction authors often face a difficult task in incorporating skepticism into their works. After all, they're usually science fiction authors for a reason, and they want to incorporate a key part of the scientific mindset into their works. But what are you supposed to do when that mindset would just make any character who possesses it spend the entire story repeatedly pointing out that the entire story is impossible? There are two options - either you modify the boundaries of the character's skepticism to incorporate whatever impossible science works in this universe...or you just sort of drop a rational skeptic from our world into this science fiction landscape more or less unaltered. And that's where things tend to get a bit weird.

Becauseit'sme, I've got to crowbar an Isaac Asimov reference in somehow. In this case, the Good Doctor actually makes things fairly easy, since he introduces a character in Foundation and Earth who actually calls himself a Skeptic, with the capital "S" and everything. This man, the wonderfully named Vasil Deniador, provides a fairly workable definition for what being a skeptic might mean in a universe of interstellar travel and a dead man's equations directing the course of history, along with why skeptics aren't particularly well-liked:

In 1955, Isaac Asimov wrote "The Portable Star", a story he considered so bad, so sexy,…
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"I accept only what I am forced to accept by reasonably reliable evidence, and keep that acceptance tentative pending the arrival of further evidnce. That doesn't make us popular."
"Why not?" said Trevize.
"We wouldn't be popular anywhere. Where is the world whose people don't prefer a comfortable, warm, and well-worn belief, however illogical, to the chilly winds of uncertainty?"

That's all well and good, but what about characters who cling to skeptical beliefs that make perfect sense in our world - one in which there is zero evidence for alien visitations, paranormal events, or anything else beyond the laws of physics - but seem extremely foolish in universes where fantastical elements run rampant? Let's examine a group of people who would be quite reasonable if they showed up around here, but just seem hopelessly contrary and silly in their own worlds.

Reed Richards, Marvel Comics

Mr. Fantastic belongs to a certain class of superheroes in both the Marvel and DC Universes who just utterly refuse to accept any of the incredible things around them as magical or otherwise unscientific. Of course, when your definition of "science" includes super-stretchiness, surrounding yourself with flames without burning up, turning invisible with just a thought, and transforming into a walking, talking rock...well, I suppose you can justify just about anything as scientific. Even so, when a guy who actually calls himself The Sorcerer Supreme is one of your closest allies, and when said Sorcerer Supreme has used stuff that really, really looks like magic to save the day on countless occasions, you'd think that maybe it's time to concede the point and move on.

Another notable example of this is the Golden Age Starman, Ted Knight. During his days on the old Justice Society of America, he regularly teamed up with Dr. Fate, who much like Dr. Strange was known to use quite a bit of magic in his crimefighting approach. There was also his occasional ally the Spectre, who is mostly remarkable because he's the embodiment of God's vengeance. Even so, Ted Knight remained stubbornly unconvinced about the existence of magic, once explaining to his son Jack that these were all just examples of exotic, not yet understood forms of energy. How that's really any more "scientific" is kind of beyond me, but I think Clarke's Law is involved somehow.

Agents Mulder and Scully, The X-Files

Wait a second! Surely I only meant to include Agent Scully in a list of misguided skeptics, rather than both of them? Well, the thing is that The X-Files never presented the two partners as a simple dichotomy of true believer and hardened rationalist. Or at least, they didn't do that all the time. Rather, Agent Scully was a fairly devout Catholic, which would make the two switch places whenever the mystery of the week led them into territory more spiritual than extraterrestrial.

Still, Scully was perhaps more prone to taking Occam's Razor and turning it into Occam's Sledgehammer. She sometimes had a tendency to not just seek out the simplest answer, but to accept it unquestioningly even if it was unable to explain all parts of the latest mystery. I'm not sure what that is, but I'm fairly sure it's not skepticism.

The robots, Saturn's Children by Charles Stross

Stross's 2008 novel isn't just the clinching argument that you can't judge a book by its cover (my goodness, that cover), it also offers a wonderfully twisted inversion of the standard arguments between faith and skepticism. His story takes place long after humans have gone extinct, leaving behind a Solar System full of androids that have developed into a repressive feudal society. In this world, it's those who believe in intelligent design - specifically, those who examine ancient schematics and conclude a race of intelligent beings built them - who are on the side of rationalism, while those who believe in evolution have only articles of faith and the "prophetic" writings of Darwin, Dawkins, and Gould to support their view. This illustrates perhaps more clearly than any other example a basic point about skepticism - it's not what you believe to be true, but rather how you arrive at that conclusion that matters, and the evidence around you necessarily has to count for quite a lot.

Everyone who encounters Hiro, Heroes

For whatever reason, a lot of people had trouble accepting Hiro's powers as the real deal in the early days of Heroes, which might have had something to do with the fact that Hiro was one of the only characters who couldn't explain his powers in perfect English. Nathan Petrelli, for instance, once dismissed Hiro as a blathering lunatic when he tries to explain his powers, despite the fact that he himself had been flying around just a few minutes earlier. His temporal powers apparently represented some sort of invisible line in the sand for many characters, even ones with powers themselves, as the sort of thing that was just a little too ridiculous, even for Heroes. Fortunately, the show solved that little problem in later seasons by conclusively proving over and over and over again that absolutely nothing is too ridiculous for Heroes.

Professor Hayter, Doctor Who

A lot of characters in Doctor Who and its spin-offs take a rather, um, inconsistent approach to just what is and isn't impossible. The Third Doctor spent about half of the classic serial "The Daemons" explaining just why everything going on - from demons to gargoyles - was not, strictly speaking, supernatural, and indeed every Doctor from William Hartnell to David Tennant has had a predilection for declaring things impossible only to find out they weren't really. And the most recent series of The Sarah Jane Adventures found Sarah Jane scoffing at any possibility of ghostly haunting, despite the fact that she treated the (frankly ludicrous) stone tape theory as accepted fact not two series prior.

But leaving these inconsistencies on the parts of our protagonists aside, one skeptic on Doctor Who stands out from all the others, even if you have to go back to the 1982 serial "Time-Flight" to find him. Now, there was plenty of room for skepticism in "Time-Flight" - everyone who read the script, for instance, should have been skeptical it was worth making. But once the production team committed to realizing the utterly insane story of the Master stealing the Concorde in mid-air and transporting it back to the Cretaceous Period...well, it was probably time for everyone involved to just shrug their shoulders and go with the flow.

Nigel Stock's Professor character, however, refuses to be taken in by the Master's psychic illusions, which makes the rest of the crew and passengers of the Concorde believe they have landed in Heathrow. That's reasonable enough, but he then also refuses to believe he's really in the Cretaceous period, speculating they're the victims of some sort of ultrasonic Soviet attack. Again, that's not a ridiculous hypothesis, but he then dismisses the Doctor and his companions as completely insane, even attempting to break Nyssa's "conditioning."

Even then, I suppose that's not so bad, but when confronted with the alien Plasmatons the Master has enlisted in his aid, he just assumes they are Soviet soldiers in disguise, despite the fact that they look like this. He also uses the fact that the Master's crystal ball has a few electrical circuits inside it as proof that everything else is just an elaborate trick. Basically, he spends the majority of the story as a grumpy, contrarian windbag who does nothing more useful than tell the Doctor he's insane. But what else could you really expect from a character who is actually called Professor Hayter?

Allen Carpent(i)er, Inferno by Larry Niven and Jerry Pournelle

Science fiction author Allen Carpentier (real name Carpenter) finds himself in a bit over his head when a fall from a balcony sends him to somewhere that looks suspiciously like Hell in Niven and Pournelle's 1976 update of Dante's Inferno. (We mentioned Kurt Vonnegut's cameo in it yesterday.) Despite pretty much insurmountable evidence to the contrary (and then some), Carpentier stubbornly refuses to believe he's actually in Hell, instead preferring the hypothesis that he's been placed in an elaborate simulacrum by omnipotent aliens, and he comes up with a series of increasingly implausible explanations to keep this theory alive. It takes him the entire book to finally accept the reality of his situation, although to be fair there might be more going on here than mere misplaced skepticism - it appears that denying the fact that he's in Hell is the only thing keeping him from going insane. Under the circumstances, I can cut him some slack.

Man and the man, The Hitchhiker's Guide to the Galaxy

This legendary passage from the first Hitchhiker's book points out how being overly skeptical* can go seriously wrong:

"I refuse to prove that I exist," says God, "for proof denies faith, and without faith I am nothing."

"But," says Man, "the Babel fish is a dead giveaway isn't it? It could not have evolved by chance. It proves that you exist, and so therefore, by your own arguments, you don't. Q.E.D.."

"Oh, that was easy," says Man, and for an encore goes on to prove that black is white and gets himself killed on the next zebra crossing.

*If telling God to his face that he doesn't exist isn't skepticism, then I'm not sure what is.

Douglas Adams had even more fun with people who take too far the skeptical impulse to not believe everything you hear in The Restaurant at the End of the Universe. He introduces the real Ruler of the Galaxy, who is perfect for the job because he lives alone in a shack (well, he's got a cat) on an otherwise uninhabited planet and refuses to believe anything exists that he can't see with his own eyes. This means that he is, by definition, the fairest person in the entire universe, although how this translates to a coherent legislative agenda is really anybody's guess.

Dr. Thirteen, DC Comics

Dr. Terrance Thirteen isn't so much the DC Universe's resident skeptic as he is its fundamentalist of unbelief. It's one thing to doubt the existence of magic, but Dr. Thirteen takes it ten steps further by refusing to believe in any of the fantastical elements of his world. Aliens - including Superman - are completely impossible as far as he's concerned, as are supernatural beings. It's almost as though he were a skeptic from our world dropped unaltered into the DCU, which makes sense because that's basically exactly what happened to him.

He was originally conceived as a standalone character for one of DC's anthology comics in the 1950s, in which he traveled America debunking supposed magic. He lived in a world very much like our own, and his skeptical instincts were always proven correct. When this series came to an end he was dropped into the wider DC universe, where his once perfectly rational beliefs suddenly turned him into a laughingstock. Clinging desperately to his belief in the mundane in the face of overwhelming evidence to the contrary (including the fact that his own daughter Traci is a very powerful witch), Dr. Thirteen remains a figure of fun in the DCU.

Still, he's not totally useless - Neil Gaiman's Book of Magic posited that his total disbelief of magic actually makes it impossible for magic to affect him, and his desperate attempts to cling to normalcy and relate to his daughter while surrounded by French cavemen, ghost pirates, and Nazi gorillas in the recent Tales of the Unexpected lent him a certain warped nobility. To steal a description from elsewhere, Dr. Thirteen is really just a street smart fish out of water in a world he never made. Or a bumbling buffoon. Sorta depends on who's writing him.